This disclosure is related to metal flange plates for vessels involved in transport or storage of corrosive liquids. More particularly, it relates to metallic flange plates lined with a rigid non-metallic material impervious to corrosive liquids.
Handling of liquids in various disciplines such as chemical or petroleum processing involves storage, shipment, and transfer of material highly corrosive, or otherwise deleterious, to containment equipment made of metal. Accordingly, it is necessary to isolate the contact surfaces of the equipment from the liquid.
In the past, containment vessels, as well as flow components such as metal tubes and flanges, have been coated with rubber to isolate the contact surfaces from the corrosive liquid. These components are relatively effective, but lack durability under the arduous conditions experienced, for example, in transporting the corrosive liquid by rail or tractor trailer truck.
The rubber at the flanges and tubes is more readily susceptible to deterioration than the rubber inside the containment vessel. The enhanced likelihood of deterioration can be attributed to the frequent attachment and removal of piping components and rapid flow of corrosive liquid through the piping elements during loading and unloading.
Moreover, rubber may often harden when exposed to certain chemicals, such as hydrochloric acid (HCl), which can lead to cracks in the rubber exposing the underlying corrosive surface. When the rubber coating does experience excessive wear or failure, repair of damaged rubber coating is an expensive and time consuming process that involves scraping the rubber coating off of the metal components and then applying a new rubber coating to the metal.